Originally Posted by cheezit
if the ipr failed to stay open you engine would shut off and you would have a 100% return back to the sump.


I have had the turbo off and it looks very clean, spins freely

As far as the IRP goes, I believe, the IRP is Normally open ( when truck is off the IRP is fully open, allowing oil to route to sump)

When truck is running and a desired PSI is required the PCM closes the irp till the desired PSI (ICP signal) is reached.

When the desired PSI is not reached for a given amount of time the P2290 code comes up and only sometimes the check engine light comes on.

I believe the ICP is sending a correct signal to the PCM, and the PCM is sending a correct command to the IRP, but Sometimes the IRP is not responding to the command, Only sometimes. On start up I think the IRP is sticking in the Open position

It started a couple months ago now, I did a ton of work as said in previous posts, thought I had the problem fixed, the started a 1000 mile road trip and it started again, made it to my destination, and then while away it only happened periodically, never when the truck was cold, Ant then drove home the other day , another 1000 mile trip and no problems at all.

I will get out to shop in a couple days and hook up my AE and try to graph ICP, ICP desired etc. befor I start ripping apart.

Thanks Guys!

 

You really have to disassemble the exhaust side of the turbo to see if the vanes and unison ring are hanging. It can look clean and spin fine and still cause an over or under boost issue.

Have you replaced the IPR?

 

Don't realy have a boost issue, even when the loss of power thing is happening (low ICP) I still have boost when I put the peddle down. Turbo was new 8 months ago.

My problem is low HPO, but only sometimes, most of the time it runs fine and I have no prob getting 3600 ICP.

I have checked out ICP pig tail and its seems to be good

 

I think your on the right track. Ipr or ipr pigtail is your next step.

 

I knew you didn't have a boost issue, I was just passing on the info about checking the turbo.

Have you replaced the IPR valve? It seems to be hanging at odd times causing your issue.

 

Ill be replacing it in a couple days Too freakin cold in the shop right now -15f

Ya its kinda strange it seems to stick open when warmed up, never when cold. I would think it would stick when cold.. Oh well, I will post when I change it..

Thanks for all the help